Interestingly, other proteasome subunits were also expressed highly in EC (Figure S1) and the elevated expression of PSMA2, PSMA5, PSMC6, PSMD5, PSMD10 indicated poor prognosis of EC patients respectively (Figure S2), which revealed a crucial role of 26S proteasome in esophageal cancer. This evidence concerns the gene PSMD5 and esophageal cancer.